4, 4&#39; bis(amino-t-butyl) substituted aromatic hydrocarbons



Patented Mar. 15, 1949 4,4 BIS (AMINO-T-BUTYL) SUBSTITUTED AROMATICHYDROCARBONS William Kirk, Jr., and Richard Seyfarth Schreiber,Wilmington, Del., assignors to E. I. du Pont de Nemours & Company,Wilmington, DeL, a

corporation of Delaware No Drawing. Application April 3, 1945, SerialNo. 586,446

3 Claims. (Cl. 260-5705) This invention relates to organic aminocompounds and more particularly to diamines,

The preparation of diamines containing aromatic groups where the aminogroups are allphatic in nature requires in general at least a two-stepreaction from readily available materials, whereby a halogenatedcompound is converted to the dinitrile and thence hydrogenated to thedesired diamine.

This invention has as an object the provisio of a process wherebydiamines may be prepared in a one-step process from readily availablematerials. A further object comprises a class of diamines showingunusual and desirable properties as intermediates for linear polyamides(nylon). Another object is the preparation of a new type of linearpolyamide. Other objects will appear hereinafter.

These objects are accomplished by the following invention wherein analkenyl monoamine having at least one hydrogen on the amino nitrogenpreferably primary, of three to four carbons having the unsaturationbetween the carbons beta and gamma to the NHz group, having a terminalmethylene, CH2=, group, and having the amino group attached to onlysingly bonded carbon is reacted with an aromatic hydrocarbon of theclass consisting of benzene, biphenyl, bi-- In a preferred mode ofoperating the processv of this invention, the catalyst, an aromatichydrocarbon, and an inert solvent are put in a reaction vessel and asolution of two mols, per mol aromatic hydrocarbon, of allylorbetaethallylamine in an inert solvent is added at a temperature of 20-50C. The reaction is comp eted, after the addition of the amine iscompleted, by heating for one to three hours at 60- 80 C. The product isisolated by the treatment of the reaction mixture with water, separatingthe solvent and adding an excess of sodium hydroxide to free thediamine. The product is extracted by means of a water-insoluble solventand purified by distillation.

The more detailed practice of the invention is illustrated by thefollowing examples wherein parts given are by weight. There are, ofcourse, many forms of the invention other than these specificembodiments.

Example I In a reaction vessel containing 300 parts of anhydrousaluminum chloride there was placed 165 parts of n-hexane containing 39parts of benzene. With emcient agitation, 71 parts ofbeta-methallylamine dissolved in parts of n-hexane was added over aperiod of half an hour, the temperature of the resulting mixture being30-35 C. The reaction mixture was then warmed slowly to reflux andstirred at 68 C.

for four hours, at the end of which time the mixture was poured into amixture of 600 parts of ice and 500 parts of water. The hydrocarbonlayer was separated and the aqueous layer treated with an excess of 40%sodium hydroxide solution to free the product which appeared as an oilytop layer. The oily layer was separated and the aqueous layer extractedwith ether. The

main portion of the product was added to the combined ether extracts andthe whole dried over magnesium sulfate. After removal of the ether, thebis(amino-t-butyl)benzene distilled at 154- C./5 mm. A salt of thisdiamine with adipic acid gave the following analysis:

Calculated for C2oH34O4N2-N, 7.65%. N, 7.31%; 7.49%.

A polyamide was prepared from the above bis(amino-t-butyl)benzene andsebacic acid by dissolving the amine and acid in separate portions ofabsolute alcohol, mixing the solutions, filtering off the resultingsalt, and heating the same in an autoclave under nitrogen for one hourat 200 0., followed by heating for one to three hours at atmosphericpressure under nitrogen and at 285 C. A further heating under vacuum forthree to six hours at 285 C. has been found advisable to obtain productsof increased molecular weight. The polymer thus obtained was acolorless, transparent product and was soluble in such solvent mixturesas chloroformmethanol, methylene chloride-methanol, and aqueous alcohol.The polymer had a water-absorption of 4.4%. Previous linear polyamideswhich have been found to be soluble in the above solvent mixtures have ahigh water-absorption, i. e., above 5%. Polyhexamethylene adipamide isinsoluble in the above solvents and has a waterabsorption of 9-10%.

Found To a well stirred mixture of 333 parts of an hydrous aluminumchloride and 77 parts of hiphenyl in 380 parts of n-hexane was added asolution of 78.1 parts of beta-methallylamine in 65 parts of n-hexane at35-40 C. The mixture was warmed slowly to reflux and stirred at 68 C.for four hours. The hydrocarbon layer was decanted and the residuetreated with- 00 parts of ice. Excess 40% sodium hydroxide solution wasadded to the aqueous layer and the main portion of the product separatedoff as an oily top layer. The remainder was extracted with ether and thewhole dried in ether over magnesium sulfate. After removal o f .theether,. the bis(amino-t-butyl) biphenyl distilled "at 207.210 C./1 mm.to yield 77 of the theoretical-amount.

An alternative method of purification is recrystallization of thediamlne using petroleum ether the diamine by adding acetic acid to anether or Xylene solution of the diamine, followed-by recrystallizationof the acetate from alcoholwater mixtures, withsubSQQllent regenerationof the diamine by aqueous'alkali, is also eifective.

Analysis: Calculated..forCzoI-IzsNz-Neutralization Equivalent1148.2;-.=C,,.821.04;v I-I,- 9.52; N, 9.45. Found: Neutralization.iEquivalent 149.3; vC, 79.67; H, 9.46; N,;9l 51.

By the condensation .of .bis(amino-.t-butyl)- biphenyl with .anequimolarzamount of .sebacic acid, by the processlabovepgivenua high:molecular weight synthetic linear polyamidewas formed which was solublein solventsuch as chloroformmethanol and methylene zchloride-methanolmixtures, from which clear, transparent v.films could ;be cast. The.unusual properties of this polymer were (a) good solubility in solventsof practical use infilm casting while .=having a water-absorption of2-3%, and (11) @good stiffness in both the Wet and dry state. This.;combination .of prop- :erties is new-in thefield of synthetic linearpolyamides.

-ExampleIII A well vagitateclirr ixture. of 333 parts of anhydrousaluminumchloride, 380.parts of n-hexane and 64 parts of naphthalene wastreated with 62.7 parts of allylamine dissolved ,in 40 parts 'ofn-hexane. The temperature was kept. at 25-30 C. during the addition ofthe amine and'theri slowly raisedto-68 C. Afterrefluxing the reactionmixture while stirringfor 1.5 hours, the'mixture was poured into amixture of 1000-partsof .ice in 1000 parts of water. The aqueoussolution .was treated with anexcess of 40% sodiumhy- .droxide solutionand the oilyvtop layer drawn- 01T. The remainingoil was .extracted withether and the main portion of the .oilgadded to the ether extracts,dried and distilled. The bis(beta aminoisopropyl) naphthalene distilledat ZOO-208 C./2 mm.

Example I V A well agitated mixture of'333 parts of anhydrous aluminumch1oride,"91 parts of bibenzyl, (1,2-diphenylethane), and f380i'parts ofn-hexane was mixed with a solutionof 7138 parts of betamethallylamine in65-pai ts ofh-hexane at 40- 45-C. The reaction mixture was stirredandrefiuxed for one hourlafter the addition was completed.This:mixturewaszthentreated with 1000 parts of ice and 1000zpartsof'watenandstheuproduct precipitated by the additionzof iamexcess 50fsodium hydroxide solution. The bis(amino-tbutyl) bibenzyl was extractedwith ether. Evaporation of the ether gave a product which, uponrecrystallization, had a melting point of 135-136 C. and the followinganalysis:

Calculated for C22H32N2Neutra1izati0n Equivalent, 162.2; C, 81.48; H,9.88; N, 8.64. Found: Neutralization Equivalent, 164.8; C, 81.92; H,9.88; N, 8.03.

This diamine was reacted,according to the method set forth in the lastparagraph of Example I above, with sebacic acid to give a linearpolyarnide having an intrinsic viscosity of 0.82. The inventionisgeneric to the reaction of an ethylenically-unsaturated amine,preferably a :primaryamine, with an aromatic hydrocarbon :(0roxy.derivati ve.thereof) having a plurality of ;:reaotive nuclear:hydrogens, preferably benzene, ':-biphenyl, naphthalene, bibenzyl ordiphenylas the solvent. Precipitation of the acetateof T methane inthe-presence of a Friedel-Crafts catalyst, preferably a polyvalentelement halide Friedel-Crafts catalyst, including aluminum chloride,:boron trifluoride, ferric chloride, etc. Aluminum chloride is.kpreferred. The amine is reactedin .the .proportion .of 12.10 to 2.5.OIiIIlOlB moles, .per mole i of .the hydrocarbon, .in the .presence of,a solvent .which .is inert .to vthe Friedel- Crafts catalyst as.wellias to .the amine. .Saturated aliphatic hydrocarbons :are preferredfor solvents. The reaction is carriedout ata .temv.perature usuallyirom,50-,-.1 00 0., although .tem- .peratures as low ,as 0' C..andtemperatures up .to 150 C. may be employed; .the'ihighertemperaturesespecially duringthe laterstages of thereaction. The time.of reaction .(usually 0.5 to 4 .0 hours) is dependentupon .the amountof reactants and rate .of heating. The catalysts should be employed in aration of at least one mole .per mole ofthe amine.

0 The novel diamines of this invention have the wherein Ar is a:divalent .aromatic radical having its free valencesstemmingefromnuclear carbon, .i. e., "bonded through nuclear :carbons to :theC-CHzNI-Iz .groups .and .preferably is selected from the group iconsisting .of the CsH4,

- 7C6H4CH2C6H4 -'Cs-H4CeH/i, -C6H4CH2CH2C6H4, vand Cl0H6- radicals andR, is hydrogen or .alkyl of up .to six carbons, .preferablymethyl.Theproduct of.the invention is predominantly the 1,4 product.-Thepure'l-A product may .beseparated from isomers .byfractional.crystallization.

The diamines 0f;this invention are particularly useful in thepreparation ofsynthetic linearpolyamides @and :othencondensationpolymers. The unique position of the amino groups makes possible theformation of ..novel polyamides having properties whichare :verydesirable for suchapplications as waterproofcoatingcompositions forfabrics, metalsjand miscellaneous -materials, as unsupported films andfoils,.and as durablestiff fibers,;threads,.filaments, and bristles. Inaddition, these diamines .are :attractive intermediates for dyestuffsand for the-preparation of compounds for various pharmaceuticalpurposes, as bactericides, insecticides, preservative-s, medicinals,inhibitors, lubricating oil' adjuvants, etc. Theyyield .polyamidessoluble in methanol/halo genated .;methane solvent wmixtures :but of lowwater-absorption.

5 6 The above description and examples are intended to be illustrativeonly. Any modification UNITED STATES PATENTS thereof or variationtherefrom which conforms Number N me Date to the spirit of the inventionis intended to be in- 1,873,402 e b Aus- 23, 1932 eluded within thescope of the claims. 5 2,261,002 itte Oct. 28, 1982 What is claimed is:,3 29 Bruson May 25, 1943 1. A compound of the class consisting of 4,4-OTHER REFERENCES bis(amino-t-buty1) biphenyl and 4,4'-bis(aminot-butyl)bibenzyl.

Chemical Abstract, v01. 14 (1920),page 2493. b1s(amm t butynbibenzyl'Chemical Abstract, v01. 30 (1936), page 1759.

Chemical Abstract, v01. 11 (1917), page 2676.

5780. RICHARD SEYFARTH SCHREIBER' Chemical Abstract, vol. 32 (1938),page 563.

REFERENCES CITED Weston et aL, Journal Am. Chem. SOC. V01. 65

5 (1943), pages 674-676. The following references are of record in thefile of this patent:

' Certificate of Correction Patent No. 2,464,692. March 15, 1949.WILLIAM KIRK, JR., ET AL.

It is hereby certified that errors appear in the printed specificationof the above numbered patent requiring correction as follows:

Column 4,1ine 38, for the word ration read ratio; column 6,1ine 5, listof references cited, for Oct. 28, 1932 read Oct. 28, 1941 and that thesaid Letters Patent should be read with these corrections therein thatthe same may conform to the record of the case in the Patent Ofiice.

Signed and sealed this 13th day of September, A. D. 1949.

JOE E. DANIELS, K Assistant Uommz'asioner of Patents.

